Thanks Thanks:  4
Likes Likes:  7
Results 1 to 6 of 6

Thread: Bought new truck, possibly tuning.

  1. Top Of Page | #1

    Bought new truck, possibly tuning.

    I just bought a 05 from a dealer auction. They say it shifts hard under light throttle and the factory PRNDL display doesn’t work and it has as screen on the dash for s PRNDL display.

    I have no experience with the older trucks but guessing aftermarket tune.

    Anyone guess what it may have and how to return to stock as I need it to be 100% stock for my customer.

    I know it’s vague but it’s all I was told. I’m hoping I can just get a dealer to reflash the PCM.


  2. Thanks IGOTACUMMINS thanked for this post
    Likes IGOTACUMMINS liked this post
  3. Top Of Page | #2

    Re: Bought new truck, possibly tuning.

    So I figured out what the truck is.

    This is the screen I was talking about.



    The truck has a Allison 1000 6 speed swap. So I just need to diag the hard shift. Pretty sure it’s something to do with the GM adaptive learn software.


  4. Thanks IGOTACUMMINS thanked for this post
  5. Top Of Page | #3

    Re: Bought new truck, possibly tuning.


  6. Thanks IGOTACUMMINS thanked for this post
    Likes IGOTACUMMINS liked this post
  7. Top Of Page | #4
    Basic Member Benito's Avatar

    User Info Menu

    Re: Bought new truck, possibly tuning.

    Not sure you will ever really be able to get back to stock with that swap.

    You will likely have to reach out to one of the companies that do those swaps and see if they offer a tuning module so you can reflash it and hope that fixes the issue.


  8. Likes walla2k5 liked this post
  9. Top Of Page | #5

    Re: Bought new truck, possibly tuning.

    Quote Originally Posted by Benito View Post
    Not sure you will ever really be able to get back to stock with that swap.

    You will likely have to reach out to one of the companies that do those swaps and see if they offer a tuning module so you can reflash it and hope that fixes the issue.
    So I went to take it to a medium duty truck place, drove fine. And has been. So idk. Drove it 2200 miles and all of a sudden it’s perfect.

    It uses a GM TCM with Allison programming. It’s a medium duty transmission.


  10. Thanks IGOTACUMMINS thanked for this post
    Likes IGOTACUMMINS liked this post
  11. Top Of Page | #6
    Basic Member Rob_D's Avatar

    User Info Menu

    Re: Bought new truck, possibly tuning.

    Your PRND display isn't working because they flashed the ecm to a manual calibration when they did the swap.

    Looks like a neat find!


Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •